T.O. 33B-1-12-36produce duplicate fatigue cracks with identical penetrant performance characteristics. Therefore, non-qualificationsensitivity comparison tests, which are not used for qualification purposes, may be accomplished with cracked chromeplated panels.2.4.4.3.2Figure 2-10 illustrates the effects of different sensitivities by showing the indications produced on cracked chromepanels by penetrants of different sensitivity levels.Figure 2-10. Indications Produced by Penetrants of Four Different Sensitivity Levels Using Dry Developer.2.4.4.3.3Selection of the sensitivity level to be used depends on a number of factors: potential flaw size, width of opening andvolume of the discontinuity; part size, shape, surface finish and residual stress; allowable flaw size; and intendedservice of the part. The rule is to use the lowest sensitivity that will reveal the discontinuities that are large enough toaffect the integrity of the part. Difficulties can be experienced if the sensitivity level is either too low or too high. Lowsensitivity levels may not reveal critical flaws, while excessive sensitivity can result in an excessive residualbackground that would obscure any discontinuity indications or nonrelevant indications.